1. Field of the Invention
The present invention relates to a front-wheel drive device which employs a bevel gear mechanism and a planetary gear mechanism.
2. Description of the Prior Art
A conventional front-wheel drive device having a gear mechanism of the above type is shown in FIG. 5. This front-wheel drive device has the advantage that a large reduction ratio can be obtained. However, in this device, a sun gear 52 of a planetary gear mechanism 51 and a sun gear axle 55 mounting a bevel gear 54 on the output side of a bevel gear mechanism 53 are supported in a bridging manner by a front wheel axle 56 and by an outer gear casing 57 which supports the front wheel axle 56. Therefore, a cumbersome operation is required when assembling the gears. Furthermore, the construction of support of this type causes the front wheel axle 56 to protrude outward beyond the outer gear casing 57 by lengths equal to the lengths of right and left bearings 58, 59. This means that the distance from an axle 60 of the center of turning of a front wheel 61 increases, the rigidity of support of the front wheel axle 56 decreases, an increased turning force is required for steering and turning the vehicle, and a cumbersome operation is required for aligning and machining the holes for fitting bearings 58, 59 that support the sun gear axle 55.